L-1011 Active Control System remembered

Active Control System Lift DistributionThis picture was taken from here where there is a nice description of the L-1011-500 features.


I was talking with Ramin , a former Grant student now at UCB,  about the L-1011 project I spent about 13 years on.   The last few years I spent as principal engineer on one of the neat systems called the Active Control System that was used to alleviate loads on an extended wing tip of the L-1011-500.    I found some links to people that are still interested in the L-1011 even though it has long since been retired.

This is an interesting project that Curd Zechmeister is trying to do.  He is getting a complete L-1011 avionics system working for a museum.
Here was a post I responded to on the Active Control System .
Just for kicks, I googled an old paper I wrote for a conference that was published in the  Aeronautical Journal of the Royal Aeronautical Society in 1981.
The paper doesn’t seem available online.  Maybe I can find it someday and put it on line for historical reasons.  Here was a NASA bibliography reverence to it.
A82-16147 Digital active control system for load alleviation
for the Lockheed L-1011. G. E. Bendixen (Rockwell International
Corp., Cedar Rapids, IA), R. F. O’Connell, and C. D. Siegert
(Lockheed-California Co., Burbank, CA). Aeronautical Journal, vol.
85, Nov. 1981, p. 430-436. 5 refs.
A digital active control system (ACS) is described which is used
to reduce maneuver and gust loads in the extended-wing L-1011
TriStar, permitting improved aircraft performance with minimal wing
structure changes. Reliability requirements aimed at high system
availability are satisfied by means of a dual-dual, fail operational
system architecture in which each of the two ACS computers
contains two digital processors. The digital computer provides for
control of the aileron servos, self-test capability and redundancy
management. Attention is given the compatibility of automatic and
primary flight control systems, the digital sensor data transfer
functions of the ACS computer and its Algol-like software configuration,
redundancy management, and servo and computer monitoring.
Pitch Active Control System
This was a concept studied for incorporation onto the L-1011 but  never made the cut.  Here is an interesting paper by Walt Davis et al on the subject.

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